To improve the transversal stability and lateral stiffness, this paper develops a new type of pneumatic single bending joint. The single bending joint is pneumatic composite elastomer, and its driving system combined into one. The inside of the joint is elastic rubber tube and the outside is a set of closely constraints ring suit. When supplied the air pressure, the joint bends under the action of the bending moment generated at the end of the joint. The bending experiments have been done on the static experimental device and the relation between the bending angle of joint and the air pressure is acquired.